AB0828 Differences in early-onset vs. late-onset psoriatic arthritis: data from the RESPONDIA and REGISPONSER studies.
Authors: M. Á. Puche Larrubia, M. L. Ladehesa Pineda, M. D. López Montilla, E. Collantes Estevez, C. López-Medina
Journal: Annals of the Rheumatic Diseases (2022)

Background The prevalence of late-onset psoriatic arthritis (PsA) is increasing in parallel with the progressive aging of the population. The elderly population presents a greater functional deterioration and a greater number of comorbidities than the young people. With this study we aim to find clinically relevant differences to predict the evolution and prognosis of the disease depending on the onset of the symptoms to carry out a more exhaustive follow-up. Objectives To evaluate the association of the age at onset of PsA symptoms with the characteristics and burden of the disease. Methods Observational study that includes a subgroup of 231 patients with Psoriatic Arthritis (PsA) from the REGISPONSER study (Registry of Spondyloarthritis of Spanish Rheumatology) and the RESPONDIA study (Ibero-American Registry of Spondyloarthropathies). Patients with less than 10 years of disease duration (since the first symptom) were selected so that the sample was homogeneous. Patients were divided into two groups according to the age of PsA onset (early-onset: ≤40 years old and late-onset: ≥60 years old). The characteristics and burden of the disease were compared using the Student’s t-test/Mann-Whitney U test for quantitative variables or using the chi-square/Fisher test for qualitative variables. Results 411 patients were included [early-onset 179 (77.5%); late-onset 52 (22.5%)]. There was a higher percentage of men in the late-onset group compared to the early-onset group [94 (62.3%) vs. 38 (86.4%), p = 0.003]. The diagnostic delay was shorter in those whose onset of the disease was late [1.5 (2.7) vs 4 (7.7), p=0.036], as well as the duration of the disease [2.9 (2.4) vs 4.2 (2.7), p= 0.012]. A lower presence of sacroiliitis was found in patients with late-onset PsA [6 (12.2%) vs 58 (32.6%), p=0.005] as well as enthesitis [5 (9.8%) vs 44 (24.6%), p =0.023]. Regarding the comorbidities, there was a higher frequency of heart disease among patients with late-onset PsA [4 (7.8) vs 0 (0), p=0.000]. No statistically significant differences were found between kidney and lung disease. Regarding the outcome measures, the BASFI score was higher in the late-onset group [3.3 (2.5) vs. 2.2 (2.2), p=0.002]. The late-onset group had a lower FSF12 component [34.6 (8.7) vs. 38.7 (10.5), p = 0.001]. The radiographic indices measured by BASRI showed worse results in those patients with late-onset disease both in the spine [2.9 (3) vs 1.6 (2), p=0.020] and in the total BASRI [3.4 (3 .4) vs 1.9 (2.4), p=0.012]. Conclusion Our study suggests that the age of onset of PsA was associated with the different characteristics of the disease. Patients with late-onset PsA were more frequently males, showed worse functionality and more structural damage in comparison with early-onset PsA. Sacroiliitis and enthesitis were found less frequently in the late-onset group. Quality of life, disease activity and treatments taken were not associated significantly with age of onset. Table 1. Description of different characteristics across two groups: early and late onset Early-onset N=179 n (%)=77.5 Late-onset N=52 n (%)=22.5 p-value Sex (male) 94 (62.3) 38 (86.4) 0.003 Age (SD) 38.7 (9.3) 71.3 (7.5) 0.000 Enthesitis 44 (24.6) 5 (9.8) 0.023 Dactilytis 36 (20.1) 9 (17.6) 0.695 Sacroiliitis 58 (32.6) 6 (12.2) 0.005 Diagnostic Delay, mean (SD) 4 (7.7) 1.5 (2.7) 0.036 Disease Duration, mean (SD) 4.2 (2.7) 2.9 (2.4) 0.012 Arthritis (lower limbs) 118 (65.9) 33 (64.7) 0.872 Arthritis (upper limbs) 82 (45.8) 31 (60.8) 0.059 BASDAI, mean (SD) 3.9 (2.5) 3.8 (2.4) 0.932 BASFI, mean (SD) 2.2 (2.2) 3.3 (2.5) 0.002 ASDAS, mean (SD) 2.3 (1.1) 2.3 (0.9) 0.894 FSF12, mean (SD) 38.7 (10.5) 34.6 (8.7) 0.001 MSF12, mean (SD) 47.7 (10.6) 49.3 (9.2) 0.341 BASRI spine 1.6 (2) 2.9 (3) 0.020 BASRI total 1.9 (2.4) 3.4 (3.4) 0.012 ESR mm/h, mean (SD) 17.2 (14.2) 23.9 (19.1) 0.005 csDMARDs (ever) 111 (62.7) 31 (63.3) 0.943 bDMARDs (ever) 21 (11.9) 3 (6) 0.234 Disclosure of Interests None declared